General Cardiology Pearls

Platypnea is shortness of breath that occurs when standing or sitting up and is relieved while laying supine (opposite of orthopnea).

Platypnea occurs in settings including pulmonary arteriovenous malformations (hepatopulmonary syndrome) and left atrial myxoma.

The classic triad of symptoms from aortic stenosis is dyspnea on exertion, angina on exertion and syncope on exertion.

The survival in patients with symptomatic severe aortic stenosis who do not undergo aortic valve replacement is 2, 3 and 5 years in patients who present with dyspnea, syncope and angina respectively.

Aortic valve replacement is indicated in severe aortic stenosis when symptoms develop or left ventricular systolic dysfunction occurs.

Aortic stenosis is associated with small intestinal angiodysplasia which can cause GI bleeding. This is termed “Heyde’s syndrome” and resolves after aortic valve replacement. The mechanism is thought to be related to shearing of the von Willebrand factor as blood courses through the stenotic aortic valve.

Transcatheter aortic valve replacement (TAVR) is indicated in patients with severe symptomatic aortic stenosis at any level of surgical risk.

The mean pressure gradient and the aortic valve area are the two measurements used on echocardiography to determine the severity of aortic stenosis.

Severe aortic valve regurgitation causes multiple peripheral signs due to the high stroke volume present in this condition (see Aortic Regurgitation Topic review).

Aortic regurgitation and other high output states (sepsis, hyperthyroidism, arteriovenous malformations as occurs in Paget’s disease) cause a widened pulse pressure.

Functional mitral regurgitation occurs when the mitral annulus is dilated, usually from left ventricular enlargement. This results in a centrally directed regurgitant jet.

Organic mitral regurgitation occurs when there is a problem with the mitral valve leaflets themselves. If an anterior leaflet problem is present, the regurgitant jet is directed posteriorly. If a posterior leaflet problem is present, the regurgitant jet is directed anteriorly.

The ejection fraction in a patient with severe mitral regurgitation should be 65% or greater. If less than 65%, then left ventricular systolic dysfunction may be present possibly due to the mitral regurgitation itself.

The most common cause of mitral valve stenosis is rheumatic valvular disease. Other causes include age, chest radiation, congenital heart disease and autoimmune diseases.

The Wilkins echocardiographic score is used to determine if a person with rheumatic mitral valve stenosis is a candidate for percutaneous mitral balloon valvotomy.

Tricuspid regurgitation rarely requires surgical intervention; however, it can be indicated when severe and causing symptoms of right heart failure refractory to medical management.

The CHA2DS2 VASc score or the CHADS2 score are used to determine thromboembolic risk in patients in atrial fibrillation and help to determine whether aspirin or full anticoagulation should be used.

The causes of atrial fibrillation can be remembered with the mnemonic PIRATES:

• Pulmonary embolism, pulmonary disease, post-operative
• Ischemic heart disease, idiopathic (“lone atrial fibrillation”)
• Rheumatic valvular disease (mitral stenosis or regurgitation)
• Anemia, alcohol (“holiday heart”), age, autonomic tone (vagal atrial fibrillation)
• Thyroid disease (hyperthyroidism)
• Elevated blood pressure (hypertension), electrocution
• Sleep apnea, sepsis, surgery

When deciding upon an AV-blocking agent to slow down the heart rate from atrial fibrillation, it is important to know the ejection fraction, as non-dihydropyridine calcium channel blockers such as diltiazem should be avoided if the systolic function is reduced.

Conditions that cause shock (hypotension) and pulmonary edema include acute mitral regurgitation and acute ventricular septal defects.

Avoid beta-blockers or use those with alpha blocking properties in patients with coronary vasospasm to avoid “unopposed alpha agonism” which can cause vasoconstriction and worsen the vasospasm.

ACE inhibitors/angiotensin receptor blockers (ARBs) and beta-blockers need to be titrated up slowly to their goal doses in patients with systolic heart failure in order to achieve the greatest benefit.

The most common causes of heart failure exacerbations include: medication non-compliance, fluid/sodium restriction non-compliance, arrhythmia, ischemia and progression of the primary disease process.

Treat a wide QRS complex tachycardia like ventricular tachycardia until proven otherwise.

The TIMI Risk Score can be used to predict outcomes in patients presenting with potential anginal symptoms.

Below are high-risk features that would warrant an early invasive strategy in patients with unstable angina or non-ST elevation myocardial infarction:

• Increased cardiac biomarkers (troponin, CK-MB)
• New ST segment depression
• Signs or symptoms of congestive heart failure (rales on examination, hypoxia with pulmonary edema on chest X-ray)
• Hemodynamic instability
• Sustained ventricular tachycardia or ventricular fibrillation
• Recent coronary intervention within 6 months
• Prior coronary artery bypass grafting
• High TIMI Risk Score
• Reduced left ventricular systolic function (ejection fraction < 40%)
• Recurrent angina at rest or with low-level activity
• High-risk findings from non-invasive testing

Absolute contraindications to thrombolytic therapy include:

• Prior intracranial hemorrhage
• Ischemic stroke within 3 months
• Known cerebrovascular abnormality such as aneurysm or arteriovenous malformation
• Known malignant intracranial tumor
• Significant closed head trauma or facial trauma within 3 months

Relative contraindications to thrombolytic therapy include:

• Uncontrolled hypertension (blood pressure > 180/110 mm Hg) either currently or in the past
• Intracranial abnormality not listed as absolute contraindication (ie, benign intracranial tumor).
• Ischemic stroke > 3 months prior
• Bleeding within 2-4 weeks (excluding menses)
• Traumatic or prolonged cardiopulmonary resuscitation (CPR)
• Major surgery within 3 weeks
• Pregnancy
• Current use of anticoagulants
• Non-compressible vascular puncture
• Dementi